The present invention relates to a new and improved construction of an oscillating device.
In Swiss Pat. No. 596,701 there is described an electro-mechanical oscillating device comprising an oscillating member and a spring, which has a resonant frequency of oscillation. A regulating circuit controlled by means of an inductive displacement transducer or pickup provides a forcing signal which ensures that so much electric energy is supplied to the excitation windings of two electromagnets as is lost mechanically. For this purpose the control circuit is provided with a differential element including a proportional amplifier connected thereafter, as well as with a symmetry comparator including an integrator connected thereafter. Though this oscillating device is very suitable for applications where a relatively large angular displacement is required, it is not suitable for applications where it is important for the frequency of oscillation and phase angle of the forcing signal to be as accurate as possible.